Most people don’t know a lot about David Souter. Those who’ve looked at his Wikipedia article know that he’s a Harvard and Oxford grad who went on to become an attorney general for New Hampshire. Then in 1990, he went from being appointed as a judge for the First Circuit Court of Appeals to being placed on the highest bench in the country by George H. W. Bush. Factoids aside, all people really need to know right now is that he’s a Supreme Court justice who has just announced his intent to retire, and that picking his replacement has been played up as a big deal. Well, it’s not. It’s about as big of a deal as picking the First Dog (who, by the way, is adorable).

When I say it’s not a big deal, I don’t mean to sound naïve: Not every nominee is as cute as Bo. But there’s only so much weight a Supreme Court pick carries. Think about the selection of Bo Obama. Outside of making sure the dog is hypoallergenic (gets Senate approval) and getting to choose what the dog looks like (gender, race, age), there’s not much a president can do to make sure a dog behaves the way the president wants him to without putting him on a leash and training him (you can’t really put a leash on a Supreme Court justice — at least not to my knowledge).

Still, the fact that President Obama does have the chance to pick a minority candidate (as in a woman who is of an ethnicity other than Caucasian) is a big deal: Adding some diversity to the bench is needed. And who is chosen to wear a black cloak on First Street is pretty important, judicially speaking: His or her views will influence court decisions for many years to come. But in the political context of today, the selection of Obama’s Supreme Court nominee means very little at all, for a few reasons.

The first and most obvious reason would be the affect of Souter’s retirement on the ideological balance of the Supreme Court, of which there are (tentatively) four liberals and five conservatives. Souter falls under the (relatively) liberal umbrella, and replacing him with another liberal (as may be expected from a Democratic president) will not upset the balance as it is today: We still end up with a 5-4 split.

Most of the potential nominees being floated around, however, are not that liberal. So let’s say Obama chooses a moderate (hypoallergenic) candidate, one who will easily be confirmed by the senate and likely to win him support from a few moderates in the next presidential election. There’s a good chance that even if he picks a moderate with whom he agrees on some key issues (e.g. abortion), that pick will go sour.

There have been numerous cases in the past when a president has picked a nominee and watched him or her stray slowly but surely away from his or her ideological home. This is not to say that a Republican picks a hardcore conservative and watches them go hardcore liberal (since Senate battles these days almost insure that all justice nominees are relatively non-ideological). Rather, if a president picks someone assuming they are of one persuasion, there’s plenty of evidence to suggest that that may not be the persuasion the justice will hold by the end of his or her tenure.

Prime examples of this are our friends David Souter and John Paul Stevens, a Chicago native, frat boy and Northwestern alum. Both justices were considered to be noticeably conservative before their appointment, but both have cast just about as many conservative votes as Ruth Bader Ginsburg (widely considered to be a moderate liberal, a sentiment that is backed up by her voting record). Now candidates whose ideological convictions lean strongly one way or the other seem less likely to change their minds while on the bench, but this is by no means a tautology. In any case, Obama probably won’t pick an extremely conservative or liberal candidate, and even his moderate pick isn’t guaranteed to stay moderate.

Moreover, there’s a fair chance that Obama will get the pleasure of picking one or two more justices during his presidency, making this one pick relatively small compared to the sum of all of his picks.

But regardless of how his pick(s) turns out, the likelihood that the “Obama Court” as it stands by the end of his presidency ends up deciding a landmark case with the political weight of Roe v. Wade or Brown v. Board of Education seems slim. By that point, the Court will have changed. Someone else will have retired and some other president (Republican, Democrat, or otherwise) will pick someone else to replace him or her, changing the court dynamic yet again.

Unless Obama replaces the entire court with hardcore liberals, not much is going to change once Souter is replaced: There are just far too many factors involved in Supreme Court justices’ political moods and decisions for the president who picked them to have much of an influence on the future of the court. Essentially what all of this dictates is that the choosing of Souter’s replacement is about as fascinating as picking a Portuguese Water Dog over an Irish Water Spaniel.